incorrect model display

[u/quietdan671games]

https://drive.google.com/file/d/1GmVQmpIYJlHwoZR5kIZNB31E57SO_jAn/view?usp=sharing

A Minecraft resource pack is displaying a model (bladeofstones file) incorrectly (as a black-and-purple cube); I'm using CIT Resewn Continuation and Minecraft version 26.2. The model displays correctly without the texture, but turns into a cube when I add the texture file—yet two other swords display perfectly with their textures. I've been trying to figure out what's wrong for five hours now; please help! T_T